Stock material or miscellaneous articles – Composite – Of addition polymer from unsaturated monomers
Reexamination Certificate
1998-08-20
2001-01-30
Hess, Bruce H. (Department: 1774)
Stock material or miscellaneous articles
Composite
Of addition polymer from unsaturated monomers
C428S212000, C428S195100, C427S372200, C427S385500
Reexamination Certificate
active
06180256
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a heat shrinkable ink jet recording medium and a method for preparing the medium. The present invention further relates to a method for preparing an article using the heat shrinkable ink jet recording medium.
BACKGROUND OF THE INVENTION
There are many applications of consumer desktop printing in which consumers use ink jet printing. The low cost, high speed and full color output associated with desktop ink jet printing make such methods valuable for the production of brochures, reports, cards, stickers, photos and various other products. However, the inability of desktop ink jet printer feed mechanisms to accommodate thick substrates limits the media selection to those generally less than 10 mils thick. However, there are many ink jet printing applications for printed media greater than 10 mils thick. Often, these applications are accomplished by transfer printing. U.S. Pat. No. 5,148,196 to Spector discloses a system for converting a printable sheet of heat-shrinkable, synthetic plastic film material into a custom-made miniature of a selected individual, using a video camera and television monitor to transfer an image of the individual to an associated printer which impresses the image on the film in a scale appropriate to its dimensions. The film sheet is then shrunk by heating to produce a miniature.
SUMMARY OF THE INVENTION
The present invention provides a heat shrinkable ink jet recording medium, and a method for preparing the medium, that can be shrunk after printing to construct many useful articles, such as toys, jewelry, ornaments, art pieces, etc., which articles are not possible or desirable to construct from a transfer process. An ink jet printer is used to print the articles onto the medium using original designs created with commercially available software, images selected from clip-art or down-loaded from the Internet, scanned photographs, etc.
The present inventive heat shrinkable ink jet recording medium comprises a heat shrinkable base substrate and a heat shrinkable ink jet ink receptive coating layer applied to a printable surface of the base substrate, wherein the base substrate and the ink jet ink receptive coating layer are shrinkable in uniform proportion in all directions. The base substrate is polystyrene or biaxially oriented polypropylene. The ink jet ink receptive coating layer comprises (1) a flexible resin having a glass transition temperature lower than that of the substrate to which the coating is applied and a water absorptivity of greater than 50% by weight, and (2) an adhesion promoter that is a graft copolymer of hydroxyethyl methacrylate and methyl methacrylate.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a heat shrinkable ink jet recording medium comprising a heat shrinkable base substrate and a heat shrinkable ink jet ink receptive coating layer applied to a printable surface of the base substrate. The base substrate and ink jet ink receptive coating layer are shrinkable in uniform proportions in all directions, and are shrinkable after printing to produce the article of the present invention. In the present inventive medium, the substrate is preferably in the form of a sheet of a shrinkable material such as polystyrene or biaxially oriented polypropylene. More preferably, the base substrate is shrinkable in a “x” dimensional direction in an amount of up to about 61% and is shrinkable in a “y” dimensional direction in an amount of up to about 41% after heating the base substrate at about 120° C. for about five minutes, and wherein the “x” dimensional direction and the “y” dimensional direction are perpendicular to each other and are in a plane formed by the base substrate. Concurrent with its shrinking in the “x” and “y” dimensional direction, is an expansion of the base substrate in a “z” dimensional direction that is perpendicular to the plane formed by the base substrate. That is, upon heating the base substrate it not only shrinks in both the “x” and “y” dimensional directions, but also expands in a “z” dimensional direction to become both dimensionally smaller (in the “x” and “y” dimensional directions) and thicker (in the “z” dimensional direction).
The ink jet ink receptive coating used to prepare the present inventive medium preferably comprises (1) a flexible resin having a glass transition temperature lower than that of the substrate to which the coating is applied and a water absorptivity of greater than 50% by weight, and (2) an adhesion promoter that is a graft copolymer of hydroxyethyl methacrylate and methyl methacrylate.
When in the instant invention, the substrate selected is polystyrene, suitable flexible resins that can be used in the ink jet ink receptive coating layer include poly(2-ethyl-2-oxazoline), poly(ethylene oxide), poly(tetrahydrofuran), poly(1,3-dioxolane), and poly(vinylmethylether), each of which have a glass transition temperature of less than that of polystyrene (i.e., about 100° C.).
The adhesion promoter used to prepare the ink jet ink receptive coating layer of the present invention is preferably a graft copolymer wherein hydroxyethyl methacrylate is grafted on a backbone of methyl methacrylate.
While not being bound by any theory of how the instant invention works, the present inventor believes that when polystyrene, or another suitably shrinkable substrate material, is used as a substrate in the inventive medium, it swells in the presence of solvents used in the inventor's coating solutions, such that the adhesion promoter can attach to the swelled surface of the substrate and remain attached thereto when the solvent is removed by drying.
The purpose of the flexible resin in the ink jet ink receptive coating is to prevent cracking of the ink jet coating layer when the coated shrinkable substrate is later shrunk. Thus, the flexible resin used in the inventive media should not be a resin that cracks or crazes under strain. Also, the chosen flexible resin should possess a glass transition temperature lower than that of the substrate to which the ink jet ink receptive coating is applied, and should possess a water absorptivity of greater than 50% by weight in order to ensure adequate ink absorptivity for the produced ink jet ink recording medium.
The heat shrinkable ink jet recording medium of the present invention is prepared by producing the ink jet ink receptive coating as described herein, applying the coating to a surface of a heat shrinkable base substrate, and drying the coated base substrate to produce the shrinkable ink jet recording medium. The coating can be applied using any suitable means including but not limited to roller coating, extrusion coating, wire-bar coating, dip-coating, rod coating, doctor coating, or gravure coating. Such techniques are well known in the art. The coating layer is applied to the base substrate in an amount of from about 4 to about 25 grams per square meter (g/m
2
). The coated substrate is dried in an oven at a temperature of about 100° C. for about 1 minute.
An article is produced with the prepared heat shrinkable ink jet recording medium of the present invention by printing a desired image on the medium with an ink jet printer and heating the printed at a sufficient temperature and for a sufficient time to cause the heat shrinkable ink jet recording medium to heat shrink and thereby form said article by shrinkage of the recording medium in both “x” and “y” dimensional directions, and expansion thereof in a “z” dimensional direction, as previously described herein. A typically suitable temperature and time for heating a printed medium of the present invention to thereby form an article of the present invention is, for example, about 120° C. for about 5 minutes. This is true, for example, when the base substrate is a sheet of a shrinkable material such as polystyrene or biaxially oriented polypropylene.
The following examples are provided in an effort to aid those desiring to practice the instant invention. These examples are in no way to be construed as limited to the presen
Arkwright Incorporated
Birch & Stewart Kolasch & Birch, LLP
Grendzynski Michael E.
Hess Bruce H.
LandOfFree
Heat shrinkable ink jet recording medium does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Heat shrinkable ink jet recording medium, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Heat shrinkable ink jet recording medium will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2537126